Laterally movable door mechanism and method



Aug. 1967 R. L. LANDIS ETAL 3,334,441

LATERALLY MOVABLE DOOR MECHANISM AND METHOD Filed July 15, 1965 5 Sheets-Sheet l //2 I i ii :l 2

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l: g 24 26 30 E g n 34 Z v50 n3? INVENTORS A 3 38 fi ROBERT L. LIANIDIS EDWARD 0.0 BRIEN Fig- I BY ATTORNEY Aug. 3, 1967 R. L. LANDIS ETAL LATERALLY MOVABLE DOOR MECHANISM AND METHOD Filed July 15, 1965 5 Sheets-Sheet 2 INVENTORS ROBERT L. LANDIS EDWARD D. O'BRIEN ATTORNEY Aug. 8, 1967 R. L. LANDIS ETAL 3,334,441

LATERALLY MOVABLE DOOR MECHANISM AND METHOD Filed July 15, 1965 5 Sheets-Sheet 5 2022 r l W U 204 m 223 w INVENTORS ROBERT L. LA'NDIS BY EDWARD D. O'BRIEN M g. xwLw L ATTORNEY g- 3, 1957 R. L. LANDIS ETAL 3,334,441

LATERALLY MOVABLE DOOR MECHANISM AND METHOD FiledJl lly 15, 1965 5 Sheets-Sheet 4 i n i Fig. IO

INVENTORS ROBERT L. LANDIS BY EDWARD D. O'BRIEN- Um g. Lww- I ATTORNEY g- 8, 1967 R. L. LANDIS ET'AL 3,334,441

LATERALLY MOVABLE DOOR MECHANISM AND METHOD Filed July 15, 1965 5 Sheets-Sheet 5 ROBERT L..LAND|S BY EDWARD D. O'BRIEN Wm, S LwLmp ATTORNEY United States Patent 3,334,441 LATERALLY MOVABLE DOOR MECHANISM AND METHOD Robert L. Landis, Los Altos Hills, and Edward D. OBrien,

Woodside, Califi, assignors to The Landis Sales Company, Inc., Los Altos, Caliih, a corporation of California Filed July 15, 1965, Ser. No. 472,218 17 Claims. (Cl. 49-220) ABSTRACT OF THE DISCLOSURE An actuating mechanism for laterally moving a sliding door of the plug type into and out of the door opening utilizing four independent crank arms, each rotatably journ-aied at opposite end portions to the sliding door and the supporting door track, respectively. "Each crank arm includes a cam follower means disposed between opposite end portions which is operatively engaged by a horizontally movable cam carried by the sliding door which rotates the crank arm about the journaled door connection for laterally moving the sliding door.

This invention relates to flush type doors for vehicles (also known as plug doors), and more particularly to a mechanism for moving a door of this type laterally into and out of a recessed door opening for sealing and un sealing.

Flush type doors have found wide application for closing the recessed door opening in box cars, trucks and the like, particularly where the opening is of large size. Because of the large size opening to be sealed, the problem of laterally moving a flush type door in and out of the door opening is accentuated by the fact that these doors may have an area of 60 to 100 square feet and weigh :between 1500 and 2000 pounds. To expose the door opening, the flush type door is first laterally moved to unplug the door opening and thereafter moved parallel to the wall of the vehicle to uncover the door opening. To close the door opening, the door movement is reversed. The lateral movement of the door into and out of the door opening requires the application of large forces to effectively form and break the seal.

Flush type doors are usually supported for longitudinal movement between a pair of door tracks, secured to and extending along the side sill structure of the car, and straddling the door opening. The flush type door has rotatably secured to it a pair of lower and a pair of upper crank arms which guidingly and supportingly engage the door tracks straddling the door opening.

In prior art flush type doors, a pair of vertically extending pipes are rotatably mounted, by means of suitable brackets, to the outside of the door, and one end of the crank arms is rigidly secured to opposite ends of the pipes. The other end of the crank arms is secured against lateral motion by guiding engagement with the upper and lower door tracks.

Heretofore a number of mechanisms have been employed to laterally move the flush type door in and out of the recessed door opening, all mechanisms having in common the utilization of the rigid pipe connection between the upper and lower crank arms. One mechanism comprises the utilization of a long lever arm, integrally attached to each pipe, to rotatethe pipe and thereby the crank arms laterally move the door into the door opening. To securely seal the door into the recessed opening and to assist in the last portion of lateral travel, the ends of the lever arms are placed into a screw operated saddle, mounted to the outside of the door between the pipes, to provide a further mechanical advantage. When the door is opened, the seal has to be broken by hand by rotating the crank arms by way of the pipes since the screw operated saddle only assists the lever arms in the closing direction.

Another mechanism used heretofore is the utilization of a rod on the car door with offset wedges which engaged female receptacles mounted upon the side of the car and which could be hand cranked to provide the last inch of travel for final sealing. Before this mechanism could only be employed for final sealing, the flush type door had to be manually moved into the door opening and only the last inch of closing was taken care of by the mechanism. This mechanism likewise provides no mechanical advantage for opening the door, and if the gasket is frozen, it is almost impossible to open the door.

These prior art flush type door mechanisms have certain other limitations which include the: very great muscular effort required to close and open these doors, the requirement for screw type saddles, long lever arms, wedges and the like, which are difficult to accommodate outside the car or door within the limitation set for the overall permissible width, the cost-attendant with connecting the upper and lower crank arms across the height of the door, and the difficulties in properly adjusting the angular position of the upper and lowercrank arms with respect to the pipes so that turning of the pipes would afiord even sealing around the door opening.

Consistent with the above, the general object of the invention is to provide an improved laterally movable door mechanism fora flush type door.

It is another object of this invention to provide a laterally movable door mechanism which provides a mechanical advantage in both directions of lateral movement, that is, a mechanism which facilitates the sealing and the unsealing of a flush type door.

Another object of the invention is to provide a flush type door mechanism for laterally closing and opening a door opening requiring a minimum of muscular eifort.

It is a further object of this invention to provide an improved flush door type door construction, utilizing cams and cam followers, which are easily and permanently adjusted after installation of the door for uniformly sealing around the perimeter of the recessed door opening.

It is still a further object of this invention to provide a combined opening and closing mechanism for a flush type door which obsoletes the requirement for an operator to manually push the door into and out of the recessed door opening.

It is still another object of this invention to provide flush type door construction which is simpler, more economical in use, and less expensive in manufacture than flush type door construction used heretofore and which requires no lever arms or brackets mounted to the outside of the car, or the car door, so that the overall width is minimized.

It is still another object of this invention to provide a laterally movable door mechanism in which the operative parts are housed in the upper and lower car door channels and are thereby protected from direct contact with the elements and from other damage.

It is a further object of this invention to provide a laterally movable door mechanism which allows the door to be longitudinally moved against a stop means to a predetermined position from which lateral movement into the door opening may be started without the need for careful trial-and-error positioning.

The instant invention solves the above-mentioned problems and accomplishes the stated objects by providing a laterally movable door mechanism which easily and effectively moves a flush type door into and out of the door opening with the application of a minimum of muscular effort. The laterally movable door mechanism of this invention provides approximately the same mechanical advantages for sealing and unsealing the door, and results in the application of a closing and opening force which is substantially uniformly distributed along the perimeter of the door.

In one embodiment of the invention, each of the crank arms is provided with a cam follower and the flush type door carries a longitudinally movable cam which engages the cam follower. Longitudinal movement of the cams results in the application of a turning torque on the crank arms which rotates the crank arms about their pivot points with respect to the door, causing lateral motion of the door.

Briefly, the laterally movable door mechanism of this invention utilizes four independent crank arms, each rotatably journaled, at opposite ends, to the door and the supporting door track. Each of the crank arms is provided with a cam follower which engages a longitudinally movable cam supported by the door. The cams are connected to a cam actuating means. Upon moving the cams in one direction, they engage the cam followers to cause rotation of the crank arms in one direction resulting in the lateral motion of the door into the door opening. Upon moving the cams in the other direction, they engage the cam followers to cause rotation of the crank arms in the other direction to laterally move the door out of the opening. The term laterally as used herein does not mean to imply that the door has no longitudinal component of motion when moved into and out of the door opening, but rather that the motion is primarily lateral as will be explained more fully in the ensuing description.

Further objects and advantages of the present invention will become apparent to those skilled in the art to which the invention pertains as the ensuing description proceeds.

The features of novelty that are considered characteristic of this invention are set forth with particularity in the appended claims. The organization and method of operation of the invention. itself will best be understood from the following description when read in connection with the accompanying drawings in which:

FIGURE 1 is an elevational view of an exemplary railroad car equipped with a flush type door constructed in accordance with the present invention.

FIGURE 2 is a fragmentary, perspective view, partially in phantom outline to expose operative parts, of the front wall portion of a railroad car having a recessed opening which is equipped with a flush type door incorporating the laterally moving door mechanism embodying the instant invention.

FIGURE 3 is an enlarged horizontal section taken along line 33 of FIGURE 2, and having superimposed thereon, in dot-dash lines, the position of the laterally moving door mechanism of this invention when the door is fully open and half open.

FIGURE 4 is an enlarged vertical section taken along line 4-4 of FIGURE 2.

FIGURE 5 is an enlarged vertical section taken along line 5-5 of FIGURE 2.

FIGURE 6 is an enlarged vertical section taken along line 66 of FIGURE 2.

FIGURE 7 is an enlarged vertical section taken along line 7-7 of FIGURE 2.

FIGURE 8 is an enlarged vertical section taken along line 88 of FIGURE 2.

FIGURE 9 is an enlarged vertical section taken along line 9-9 of FIGURE 2.

FIGURE 10 is a fragmentary, elevational view, partially in phantom outline to expose operative parts, of the front wall of a railroad car equipped with a flush type door having a laterally moving door mechanism in accordance with an alternate embodiment of the instant invention.

FIGURE 11 is an enlarged horizontal section taken along line 1111 of FIGURE 10, and having superimposed thereon, in dot-dash lines, the position of the laterally moving door mechanism of this invention when the door is fully open.

FIGURE 12 is an enlarged vertical section taken along line 1212 of FIGURE 10.

FIGURE 13 is an enlarged vertical section taken along line 1313 of FIGURE 10.

FIGURE 14 is a view taken along line 14-14 of FIGURE 12.

FIGURE 15 is an enlarged horizontal section taken along line 1515 of FIGURE 10.

Referring now to FIGURES 1-9, in which like reference characters designate like parts, and preliminary to FIGURE 1 thereof, reference character 20 designates a railway box car having a sidewall 22 which is provided with a recessed door opening 24. Door opening 24 has a pair of vertical door jambs 2'5 and 26, a horizontal upper edge 27 and a horizontal lower edge 28, and is dimensioned to receive a door 30 in substantially flush relationship with the box car sidewall 22.

As best seen in FIGURE 2, door 30 is supported for longitudinal movement by an upper door track 32 and a lower door track 34 which extend past opening 24 along sidewall 22 of the box car for a distance sufficiently long to allow door 30 to be moved to fully uncover door opening 24. The means utilized for hanging door 30 to tracks 32 and 34 respectively are a pair of upper crank arms 35 and 36 pivotally journaled to the upper edge of door 30 and guidingly engaging track 32, and a pair of lower crank arms 37 and 38 rotatably journaled to the lower edge of door 30 and supportingly engaging track 34.

As best seen in FIGURES 4 and 5 upper track 32 and lower track 34 are constructed of generally inverted U- shaped channel sections, which are welded or otherwise affixed to sidewall 22 at 40 and 41. One end of upper crank arm 36 has integrally connected thereto a downwardly depending spindle 42 which is rotatably journaled in a bracket 43 afiixed to an upper horizontal door channel 110 integrally afiixed to the main frame 44 of door 30. The other end of upper crank arm 36 has integrally connected thereto an upwardly depending spindle 45 which carries a roller hanger to which guidingly engages the interior of upper door track 32.

Upper crank arm 35, constructed similarly to crank arm 36, has a downwardly depending spindle 47 on one end thereof which is rotatably journaled in a bracket 48 mounted to a channel 110, and an upwardly depending spindle 4 9 on its other end which carries a roller hanger 50 for engaging upper track 32.

Lower crank arm 38 has a downwardly depending spindle 51 at one end thereof which engages a roller housing 52 having rollers 53 for engaging the horizontal surface of lower track 34 and downwardly depending guards 54 and 55 for straddling the sidewalls of track 34. The other end of lower crank arm 38 is provided with an upwardly depending spindle 56 which is rotatably journaled in a bracket 57 mounted to a lower horizontal door channel 101 integrally afiixed to door frame 44. Similarly, lower crank arm 37 is provided on one end thereof with a downwardly depending spindle 58 for engaging a roller housing 59 which seats upon lower track 34, and with an upwardly depending spindle at its other end which is rotatably journaled in a bracket 60 mounted to door channel 101.

The mechanism described so far provides the door suspension means allowing door 30 to be laterally and longitudinally moved on tracks 32 and 34. As best seen in FIGURES 4 and 5, door 30 comprises door frame 44 having riveted, welded or otherwise rigidly affixed to its outer surfaces the upper and the lower horizontal door channels and 101 and three vertical door channels 111, 112 and 113. Channels 101, 110, 111, 112 and 113 are structural in nature and impart rigidity to door 30. Mounted to the inner surface of main frame 44 is a door skin 62 which closes the opening spaces of the door frame.

Door 30 is generally of insulated construction inthe form illustrated and includes an interior door liner 61 having its side, top and bottom edges secured to door frame 44 by screws, rivets or the like. Door liner 61 has its interior space completely filled with a suitable insulation material 63. The walls of the box car 20 are similarly and insulatedly lined. The peripheral portion of door frame 44 is formed with an inwardly facing peripheral shelf 66 to which liner 61 is fastened, and which carries a door gasket sealing member 64. Similarly, recessed opening 24 is provided with a recessed outwardly facing shelf 67 which carries a further gasket member 68 which matingly engages gasket member 64 to establish a seal between door 30 and sidewall 22 when door 30 is laterally moved into opening 24.

As illustrated in FIGURES 3 for lower crank arm 37, each crank arm is provided with a cam follower having two vertical, operative camming surfaces for camm ng action with a cam which includes dogs for operatively engaging the camming surfaces. More particularly, upper crank arm 35 is provided with a cam follower 70 for operative engagement with a cam 71, upper crank arm 36 is provided with a cam follower 72 for operative engagement with a cam 73, lower crank arm 37 is provided with a cam follower means 74 for operative engagement with a cam 75, and lower crank arm 38 is provided with a cam follower means 76 having a pair of camming surfaces 69 and 102 for operative engagement with a cam 77. Cam 77 includes a cam dog 78 for engaging camming surface 69 and a cam dog 79 for engaging camming surface 102 as best seen in FIGURE 3.

The terminology employed herein, in connection with the designation of parts as cam and as cam follower, is based upon the premise that the cam is the prime mover and that the cam follower follows the cam. As will be explained, the cam is actuated for longitudinal motion and becomes the prime mover whereas the crank arm is the part actuated for ratchoidal motion by the cam. In other words, the designation here used is based on the operational performance of the two parts which provide camming action.

An upper differential rack-and-pinion assembly 80 including a pair of racks 82 and 83, and a lower differential rackand-pinion assembly 81 including a pair of racks 84 and 85, are respectively mounted inside the center portion of upper and lower channels 110 and 101. Racks 82 and 83 are respectively connected to cams 71 and 73 and racks 84 and 86 are respectively connected to cams 75 and 76.

As best seen in FIGURE 7, lower differential rack-andpinion assembly 81, protectively enclosed within channel 101, comprises a large roller chain gear 86 integral with a small pinion 87, the latter differentially engaging racks 84 and 85. Chain gear 86 is rotatably journaled about a shaft 88 which is suitably supported, on opposite sides, by door'frame 44, and a housing 89 bolted to lower channel 101. Housing 89 is provided with guide surfaces 115, 116, 117 and 118 which guidingly engage racks 84 and 85 to retain the racks in contact with pinion 87 and secure the racks against lateral motion. Lower channel 101 is provided with an opening 90 for communication with center channel 112 through which a roller chain 91, engaging chain gear 86, passes into the interior of center channel 112 which houses a cam actuating mechanism 92. Upper differential rack-and-pinion assembly 80 may be of the same construction.

Cam actuating mechanism 92, as best seen in FIG- URES 2 and 6, includes a roller chain gear 93, integrally connected to an actuating handle 94. Chain gear 93 is rotatably journaled to door frame 44 by means of housing 95 fastened to door frame 44 through a cutout portion in center channel 112. Housing 95 carries a pair of roller chain guides 96 and 97 engaging roller chain 91. Roller chain 91 is operatively connected to upper and lower differential rack-and-pinion assemblies 80 and 81 and is guided by chain guides 96 and 97 to engage chain gear 93.

Referring now briefly to the operation of cam actuating mechanism 92, which simultaneously operates upper and lower differential rack-and-pinion assemblies and 81, it is readily seen that as handle 94 is rotated clockwise, as viewed in FIGURE 2, chain gear 93 likewise rotates clockwise causing chain gear 86 to rotate counter clockwise, thereby moving racks 84 and in opposite directions to the left and right respectively, and racks 82 and 83 in opposite directions to the left and right respectively. In other words, clockwise rotation of handle 94 causes cams 71 and 75 to move to the left and earns 73 and 77 to move to the right.

FIGURES 8 and 9 show details of the support provided to a cam, such as cam 75, to secure the same against skewing motion, particularly at the point of engagement with the camming surface. The outwardly facing surface of door frame 44 is utilized as one guide surface for cam 75 by fastening rack 84 to cam 75, through a spacer member 99, so that the overall width of rack 84, connecting spacer 99 and cam 75, is equal to the width of lower channel 101. The teeth of rack 84 are shown at 100. At the place where the dogs depend downwardly from the cams, a thrust bracket is provided which is fastened to the interior of the channel enclosing the cam. More particularly, cam 75 is guided by a bracket 103 mounted against the interior surface of channel. 101 and having a thrust surface 108 in sliding contact with cam 75. Similar thrust brackets 104, 105 and. 106 provide sliding support of the operative portion of earns 77, 73 and 71 respectively. To provide dogs 78 and 79 with clearance, channels 101 and are provided with a slot opening such as shown at 107 of FIGURE 9.

The camming action of the laterally movable door mechanism of the instant invention is best understood by reference to the three successive lateral positions A, B and C of crank arm 38, illustrated in FIGURE 3. Position A shows door 30 in its fully opened position, position B shows the door in a half closed position, and position C shows the door in its fully closed position.

In position A, dog 79 of cam 77 bears against left surface 102 of cam follower 76, thereby maintaining crank arm 38 at a maximum angle with respect to the plane of door 30 and therefore the door at the maximum lateral distance from sidewall 22. As cam actuating mechanism 92 is rotated in a clockwise direction, rack 85, and therefore cam 77, move to the right as viewed in FIGURE 2, thereby releasing camming surface 102 by withdrawal of dog 79. As dog 78 is brought against camming surface 69, a clockwise torque is exerted on crank arm 38 about spindle 56 tending to rotate crank arm 38 in a clock-wise direction (as viewed in FIGURE 3) to decrease the angle between arm 38 and door 30. As cam 77 continues to move to the right, dog 78 rotates crank arm 38 further about spindle 56. Since the other end of crank arm 38 is connected to spindle 51, which is secured against lateral motion by lower track 34, rotation of crank arm 37 will result in lateral motion of spindle 56, and thereby door 30, into recessed door opening 24. In position C, dog 78 has moved all the way to the right, thereby rotating crank arm 38 to a position substantially parallel with the plane of the door 30 making the lateral separation between spindles 56 and 51 a minimum. This is the closed door position.

In the preferred embodiment of cam follower 76, camming surface 69 has its end portion 109 so shaped that dog 78 travels almost parallel thereto after door 30 is brought into its fully closed position to minimize, or even eliminate, any longitudinal forces being exerted upon cam 77 tending to open door 30. In this manner, any failure of actuating mechanism 92, or damage to the retaining means for handle 94, will not cause door 30 to open inadvertently.

Opening of door 30 is accomplished in the reverse manner namely, by rotating handle 94 in a counter clockwise direction which causes dog 78 to release parallel portion 109 of camming surface 69 and bring dog 79 into operative engagement with camming surface 102. Dog 79 exerts a counter clockwise torque on crank arm 38 tending to rotate the same about shaft 51 to laterally move shaft 56 outwardly with respect to fixed shaft 51. The above described action is simultaneously exerted by each of the four cams upon each of the four crank arms with the result that door 30 moves laterally into and out of opening 24 with rotation of handle 94.

Referring now to FIGURES ll5, in which like parts are designated by like reference characters, there is shown an alternate embodiment of the laterally moving door mechanism of this invention. Reference character 200 designates a portion of the sidewall of the railroad car formed with a recessed door opening 201 which is closed by means of a laterally movable, flush type door 202. Door 202 may be of any desired construction of a railroad car door as before, having a main frame general- .ly indicated by reference character 203 to which a skin 204 is mounted by welding or bolting or otherwise. Channel members 290, 291, 292, 293 and 294 are respectively welded, bolted or otherwise affixed to the upper, lower left, center and right portions of door frame 203 to provide a rigid door structure.

Door 202 is mounted to railroad car wall 200 by means of an upper track 206 and a lower track 207 which may be in all respects like tracks 32 and 34 of FIGURE 2. The actual connecting means utilized to support door 202 to rails 206 and 207 are a pair of upper crank arms 208 and 209 and a pair of lower crank arms 210 and 211. The pivotal mounting of crank arms 208, 209, 210 and 211 to door 202, and the guiding and supporting mounting of the crank arms to rails 206 and 207 may be of the same form and construction as explained in connection with the description of FIGURE 2.

Briefly, crank arms 208 and 209 are pivotally journaled to door 202 by means of spindles 212 journaled in brackets (not shown) mounted to upper horizontal channel 290, and guidingly supported by rail 207 by means of roll hangers 214. Similarly, crank arms 210 and 211 are pivotally journaled to door 202 by means of spindles 215 which are journaled in brackets (not shown) mounted to lower channel 291 and supportingly mounted upon rail 207 by means of roller housings 217.

As best seen in FIGURE 11, crank arm 210 incorporates a cam follower 220 of channel configuration and having a pair of facing camming surfaces 221 and 222 for engaging a dog 223 of a cam 224. Cam 224 is supported for sliding longitudinal motion within lower horizontal channel member 291 in much the same fashion as was explained in connection with the description of FIGURE 2 relating to cam 77.

The other three crank arms 208, 209 and 211 likewise incorporate a cam follower 220 of the type shown in FIGURE 11 which operatively engage cams 225, 226 and 227 respectively, each of which includes a dog 223 of the type shown in FIGURE 11. As will become better understood hereinafter, the cam followers 220 of crank arms 208 and 209 are arranged parallel with one another because cams 225 and 226 are arranged to move in the same direction. Likewise cam follower 220 of crank arms 210 and 211 are arranged parallel with one another but in a direction opposite to that of the cam followers or arms 208 and 209 because cams 224 and 227 are arranged to move in the same direction which is opposite to the motion of cams 225 and 226.

Referring now particularly to FIGURES 10, 12 and 1.3, there is shown a cam actuating mechanism 230 for operating earns 224, 225, 226 and 227 in unison for camming action with the cam follower of crank arms 210, 208, 209 and 211. Cam actuating mechanism 130 comprises a handle 131 rigidly connected to the outer flange 232 of a link chain gear 233. Gear 233 is rotatably journaled inside channel 293 by means of a pair of suitable 8 bearings 235 and 236, mounted respectively in door frame 203 and channel 293.

Roller chain gear 233 engages a link chain 240 which is operatively wound around a pair of link chain idler gears 244 and 245 housed respectively in channels 291 and 290. T 0 urge one side of roller chain 240 in operative contact with link chain gear 233, there are provided a pair of link chain guides 242 and 243. Idler gears 244 and 245 have integrally mounted thereon pinions 246 and 247 respectively.

Pinion 246 engages a rack 248 which is connected, at opposite sides, to carns 224 and 227. Similarly, pinion 247 engages a rack 249 which is connected, at opposite ends, to cams 225 and 226. As is best seen in FIGURE 13, rack 48 is supported against lateral motion between the inner surface of channel 291 and the flat end boss of chain idler 244. From the mechanism so far described it is immediately apparent that as handle 131 of cam actuating means is turned clockwise, rack 249 moves to the right and rack 248 moves to the left, as viewed in FIGURE 10, which will cause door 202 to move laterally inwards to seal recessed door opening 201.

The operation of the lateral moving door mechanism shown in FIGURES 10l5 will now be explained with particular reference to FIGURE 11, which shows crank arm 210 in the fully open position in dashed lines and in the fully closed position in full lines. As handle ,231 is turned clockwise, pinions 246 and 247 turn clockwise thereby moving rack 248 to the right and rack 249 to the left. This causes dog 223 on cams 224 and 227 to move to the left and on cams 225 and 226 to move to the right. As dog 223 moves to the left it engages camming surface 222 and exerts a counterclockwise torque on crank arm 210 about shaft 215. Since the end of crank arm 210 engaging rail 207 is laterally fixed, and since shaft 215 is laterally movable, the resulting turning motion of crank arm 210 will move shaft 215 and thereby door 202 inwardly into door opening 201. As before, camming surface 222 is provided with an extension 250 which is substantially parallel to the plane of door 202 when crank arm 210 is rotated to its closed door position so that dog 223 moves parallel to camming surface 222 after the door is closed. In this manner no longitudinal forces are exerted upon dog 223, and on cam 224, when door 202 is in the closed position.

As dog 223 is moved in the opposite direction, that is to the right as viewed in FIGURE 11, it engages the camming surface 221 urging crank arm 210 to rotate in a clockwise direction about shaft 215. In response to this clockwise torque, door 202 will move in an outward direction since the other end of the crank arm is laterally fixed.

Referring now to FIGURES 12 and 14, handle 231 of cam actuating mechanism 230 is provided, at either or both end portions, with a pivotally connected handgrip 260, pivoted about a pivot pin 261. To normally bias handgrip 260 to extend along handle .231, a biasing spring 262 is wound around pivot pin 261 with its ends bearing respectively on handle 231 and handgrip 260.

Biasing spring 262 is sufficiently weak so that only a small manual effort is required to fold handgrip 260 outwards against the force of spring 262.

Even though camming surfaces 222 of the four crank arms are provided with flat end portions 250 so that substantially no longitudinal forces are exerted upon the cams when door 202 is in the fully closed position, an additional safeguard against cam motion is provided in the form of a handle retaining bracket 263. Bracket 263 is mounted on channel 293 and includes a handgrip retaining channel 264 into which handgrip 260 falls to secure handle 231 against rotary motion. The outer surfaces 265 and 266 of bracket 263 may be slanted, curved or upwardly tapered in a manner to raise handgrip 260 for subsequent falling into channel 264 rotated past 263 for secure handle retention. This affords a convenient 9 method of rotating handle 231 towards its final locking position by means of handgrip 260 located on the end portion opposite to bracket 263. This handle retaining means also secures door 202 in its open position against accidental closing when not aligned with door opening 201.

Referring now to FIGURE 15, there is shown a door positioning means 270 and a door stop means 271 which cooperate with one another to place door 202 into the proper position for lateral motion into door opening 201. Door stop means 271 also prevents door 202 from leaving the tracks when the car is suddenly accelerated.

Door positioning means 270 comprises a cylindrical sleeve 272 containing a coilspring 273 which is retained in sleeve 272 by a pair of retaining end plates 274 and 277, each of which is provided with a central opening to clear a central plunger 275.

' Plunger 275 includes a spring engagement plate 276 forengaging spring 273 which normally biases plunger 275 to extend out of cylinder 272 for engagement with roller housing 217. Sleeve 272 is either mounted directly to track 207 or to sidewall 200, and is positioned longitudinally in such a manner that the end face of plunger 275, in its normally biased position, just touches roller housing 217 when door 202 is in its proper position for lateral closing. Since roller housing 217 remains stationary when door 202 is laterally moved from its fully open to its fully closed position, door positioning means 270 may be positioned when door 202 is in its fully closed position.

Since door 202 is very heavy, and must be brought to a stop after being longitudinally moved along tracks 206 and 207 into overlying relationship with door opening 201, a door stop means is provided which is sufiiciently rugged to withstand the impact necessary to bring door 202 to rest. Door stop means 271 also guards the door from leaving the tracks when the car is suddenly accelerated as is common during coupling and switching operations. Door stop means 271 comprises a bracket 280 which is provided with a resilient pad 281 to absorb the shock when the door is moved against the stop. Bracket 280 is bolted or otherwise affixed to sidewall 200 of the freight car and positioned in such a manner that it stops door motion before plunger 275 has moved all the way into sleeve 272 to protect door positioning means 270 against damage.

In operation, door 202 is longitudinally moved until it encounters door stop means 271. As door 202 moves against stop 271 it moves plunger 275 against the pressure of spring 273 into sleeve 272. Both the resilient pressure exerted by spring loaded plunger 275 and by pad 281 decelerates the car door to a stop. After door 202 has come to rest, spring loaded plunger 275 is constructed to exert sufiicient pressure to move the door slowly backwards into the position shown in FIGURE 15 which is the proper position for laterally moving the door into the door opening.

The laterally moving door mechanism shown in FIG- URE 2 utilizes a pair of dogs across a cam follower having a pair of outwardly directed camming surfaces, while the mechanism shown in FIGURE 10 utilizes a single dog and a pair of facing camming surfaces. Both embodiments provide satisfactory camming action and may be used exchangeably or in combination.

Further, in the arrangement shown in FIGURE 2. the lower and upper left cams are moved in the same direction and opposite to that of the lower and upper right cams. In the arrangement shown in FIGURE 10, the

. rightand left upper cams are moved in the same direction and opposite to the direction of the right and left lower cams. It is to be understood that by rearranging the crank arms and the cam actuating mechanism, any desired combination may be had. Further, instead of utilizing a roller chain in combination with rack-and-pinion assemblies, the racks may be connected to double acting hydraulic cams, either singly or in pairs, to provide cam actuation. A hydraulic high pressure system may be connected to such cams by quick connect hoses in the usual manner from a portable pressure system.

In assembling a door mechanism of the type herein described the door may be placed in situ by clamps or the like, prior to welding the cam followers to the crank arms. Thereafter the cams are moved into the position corresponding to the closed door position and the cam followers are welded to the crank arms. In this manner much time is saved in the final assembly step and the cam followers are accurately positioned, with the expenditure of little effort and without the use of highly skilled labor, to provide a uniform seal around the door perimeter.

There has been described hereinabove a laterally movable door mechanism in which the connecting crank arms are provided with camming surfaces and in which the door is provided with longitudinally movable cams for operatively engaging the camming surface to rotate the crank arms to impart lateral motion to the door. In this manner a laterally movable door mechanism is provided which not only seals but also unseals the door, affording the same mechanical advantage for motion in either direction. The door mechanism of this invention thereby accomplishes the objects set forth in this specification.

While the above detailed description has shown, described and pointed out the fundamental novel features of the invention as applied to various embodiments, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated may be made by those skilled in the art, without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

We claim:

1. In a laterally movable, sliding door for operation in upper and lower guiding and supporting door tracks to move laterally into and out of a door opening and to slide longitudinally to a position uncovering the door opening, an actuation mechanism for laterally moving the door comprising:

at least one horizontally extending upper crank arm rotatably journaled at one end portion to the upper end of the door, and having an upstanding roller hanger at the other end portion making guiding engagement wit-h the upper door track;

at least one horizontally extending lower crank arm rotatably journaled at one end portion to the lower end of the door, and having a downwardly depending roller housing at the other end portion making supporting engagement with the lower door track;

cam follower means disposed on said crank arms and extending between said end portions thereof;

cam means for camming engagement with the cam follower means of each crank arm guidingly supported by said door for sliding horizontal movement; and

cam actuating means operatively connectible to said cam means for simultaneous camming action, said camming action urging each of said c-rank arms to rotate about their journaled door connection thereby laterally moving said door into and out of the door opening in accordance with direction of sliding motion of said cam means.

2. In a laterally movable, sliding door for operation in upper and lower guiding and supporting door tracks to move laterally into and out of a door opening and to slide longitudinally to a position uncovering the door opening, an actuation mechanism for laterally moving the door comprising:

a pair of horizontally extending upper crank arms rotatably journaled at one end portion to the upper end of the door, and having upstanding roller hangers at the other end portion making guiding engage ment with the upper door track;

a pair of horizontally extending lower crank arms totatably journaled at one end portion to the lower I 1 end of the door, and having downwardly depending roller housings at the other end portion making surpporting engagement with the lower door track; cam follower means disposed on said crank arms and extending between said end portions thereof;

cam means for camming engagement with the cam follower means of each crank arm guidingly supported by said door for sliding horizontal movement; and

cam actuating means operatively connectible to said cam means for simultaneous camming action, said camming action urging each of said crank arms to rotate about their journaled door connection thereby laterally moving said door into and out of the door opening in accordance with direction of sliding motion of said cam means.

3. In a laterally movable, sliding door for operation in upper and lower guiding and supporting door tracks to move laterally into and out of a door opening and to slide longitudinally to a position uncovering the door opening, an actuation mechanism for laterally moving the door comprising:

a pair of horizontally extending upper crank arms rotatably journaled at one end portion to the upper end of the door, and having upstanding roller hangers at the other end portion making guiding engagement with the upper door track;

a pair of horizontally extending lower crank arms rotatably journaled at one end portion to the lower end of the door, and having downwardly depending roller housings at the other end portion making supporting engagement with the lower door track;

cam follower means, having vertically extending cam follower surfaces, disposed on said crank arms and extending between said end portions thereof;

cam means carried by said door for camming engagement with the cam follower surface of each crank arm, said cam means being guidingly supported by said door for sliding horizontal movement parallel to the plane of said door; and

cam actuating means operatively connectible to said cam means for simultaneous camming action, said camming action urging each of said crank arms to rotate about their journaled door connection the-reby laterally moving said door into and out of the door opening in accordance with direction of sliding motion of said cam means.

4. An actuating mechanism in accordance with claim 3 in which the cam follower means integral with a crank arm comprises a vertically extending curved rib on the crank arm with the surfaces on either side thereof forming said camming surfaces and in which the cam means associated with a cam follower means comprises a horizontally movable member having a pair of horizontally spaced apart and vertically extending dogs, each dog being disposed for camming action with a different surface of said curved rib.

5. An actuating mechanism in accordance with claim 3 in which the cam follower means integral with a crank arm comprises a vertical, substantially U-shaped channel in the crank arm with facing channel sides forming said camming surfaces, and in which the cam means associated with a cam follower means comprises a horizon tally movable member having a dog vertically extending into said U-shaped channel, opposite end portions of said dog being disposed for camming action with different channel sides for cam-ming action.

6. An actuating mechanism in accordance with claim 3 in Which said cam means and said cam actuating means comprises, in combination, a horizontally slidable cam for each crank arm, and in which the cams engaging said pair of lower crank arms are connected to a lower rackand-pinion assembly, and in which the cams engaging said-pair of upper crank arms are connected to an upper rack-and-pinion assembly, and in which said lower and said upper rack-and-pinion assemblies are actuated by a common, interlocked actuating mechanism.

7. A laterally movable door mechanism for moving a door, suspended between an upper and lower door track 5 for longitudinal sliding motion, in and out of a door opening, said door mechanism comprising:

horizontally extending upper and lower crank arms having one end portion rotatably and independently journaled to the upper and lower end of the door respectively, the other end portion of said upper and lower crank arms guidingly and supportingl'y engaging the upper and lower door track respectively;

and actuating means for simultaneously rotating said crank arms, said actuating means operatively engaging each of said crank arms at a portion which is intermediate to its end portions.

8. A laterally movable door mechanism for moving a door, suspended between an upper and lower door track for longitudinal sliding motion, in and out of a door opening, said door mechanism comprising:

horizontally extending upper and lower crank arms having one end portion rotatably and independently journaled to the upper and lower end of the door respectively, the other end portion of said upper and lower crank arms including means for guidingly and rotatably engaging the upper and lower door tracks respectively;

a pair of vertically disposed camming surfaces integral with each crank arm and intermediate its end portions;

cam means operatively engaging each camming surface,

said cam means being carried by said door for horizontal movement parallel to the plane of said door; and

means for actuating said cam means for simultaneous camming action, one of the camming surfaces on each crank arm being disposed to cause rotation of said crank arm in one direction when said cam means moves in one direction and the other of the camming surfaces on each crank arm being disposed to cause rotation of said crank arm in the other direction when said cam means moves in the other direction, whereby said door moves laterally into and out of said door opening.

9. A later-ally movable door mechanism .in accordance with claim 8 in which said pair of camming surfaces are formed by the facing inner sidewalls of a vertically extending slot and in which said cam means includes a dog operatively extending into said slot.

10. A laterally movable door mechanism in accordance with claim 9 in which said one of said camming surfaces has an end portion substantially parallel to the plane of motion of said cam means which is operatively engaged by said dog when said door is in the closed position.

11. A laterally movable door mechanism in accordance with claim 8 in which said pair of camming surfaces are formed by the outer sidewalls of a vertical rib and in which said cam means includes a pair of vertical extending dogs disposed on either side of said rib, each operatively associated with a different one of said camming surfaces.

12. A laterally movable door mechanism in accordance with claim 11 in which one of said camming surfaces has an end portion substantially parallel to the plane of motion of said cam means which is operatively engaged by the dog initiating door closing when said door is in the closed position.

13. A laterally movable door mechanism in accordance with claim 8 which includes a door stop means and a door positioning means, disposed in spaced relation to a vertical sidewall of said door opening, and affixed to the sidewall defining said door opening, said stop means and said door positioning means cooperating with one vertical edge of said door, said door positioning means including a stationary housing and a movable spring loaded plunger within said housing for moving said door longitudinally in a direction opposite said door stop means to a predetermined position when said plunger is fully extended which position allows said door to be laterally moved into said door opening, said door stop means being positioned to stop longitudinal door motion of said door when said plunger is forcibly moved into said housing by said door a predetermined distance past said predetermined position.

14. A lateral movable door mechanism for moving a door, which is guidingly supported for longitudinal motion between an upper and a lower door track to expose a door opening, into and out of said door opening, said door mechanism comprising:

a pair of upper and a pair of lower horizontally disposed crank arms having first and second end portions, the first end portions of said upper and said lower crank arms being independently and rotatably journaled to the upper and lower ends of said door respectively;

upper and lower door track engagement means guidingly and rotatably engaging said upper and said lower door tracks and connected to the second end portions of said upper and lower crank arms respectively;

cam means for each crank arm guidingly supported by said door for sliding horizontal movement parallel to the plane of said doors;

cam follower means, having at least one vertically disposed camming surface, integral with each crank arm and extending lengthwise along the crank arm between said first and second end portions and operatively engaging said cam means; and

means for simultaneously actuating each of said cam means for camming action with said camming surfaces to rotate said crank arms for laterally moving said door into and out of said door opening.

15. A lateral moveable door mechanism in accordance with claim 14 in which the means for actuating said cam means includes a raok-and-pinion assembly mounted to said door and having said cam means coupled to rack of said assembly.

16. A lateral movable door mechanism in accordance with claim 14 in which said means for actuating said cam means is mounted to said door and comprises: an actuating chain gear, a manually turnable handle coupled to said chain gear, upper and lower rack-and-pinion assemblies each having a pinion chain gear integral with its pinion, a chain operatively engaging said actuating chain gear and said pinion chain gears, said cam follower means being operatively connected in pairs to the racks of said upper and lower assemblies.

17. The method of laterally moving a longitudinally slidable door, operatively suspended between a pair of door tracks for uncovering a door opening, into and out of the door opening, said method comprising the steps of:

suspending said door from said tracks by horizontal crank arms which have one of their end portions independently and rotatably journaled to the opposed lower ends of the door, and which have the other of their end portions rotatably and guidingly received by the upper and lower door tracks respectively; and rotating the crank arms simultaneously by simultaneously applying a force to each crank arm at a portion of the crank arms which is intermediate its end portions.

References Cited UNITED STATES PATENTS 1,959,706 5/1934 Christianson et a1. 49-218 2,032,354 3/1936 Dwyer 49-220 2,108,224 2/ 1938 Hazeltine 49-220 2,5 83,646 l/ 1952 Hazeltine 49-220 DAVID J. WILLIAMOWSKY, Primary Examiner. KENNETH DOWNEY, Examiner. 

1. IN A LATERALLY MOVABLE, SLIDING DOOR FOR OPERATION IN UPPER AND LOWER GUIDING AND SUPPORTING DOOR TRACKS TO MOVE LATERALLY INTO AND OUT OF A DOOR OPENING AND TO SLIDE LONGITUDINALLY TO A POSITION UNCOVERING THE DOOR OPENING, AN ACTUATION MECHANISM FOR LATERALLY MOVING THE DOOR COMPRISING: AT LEAST ONE HORIZONTALLY EXTENDING UPPER CRANK ARM ROTATABLY JOURNALED AT ONE END PORTION TO THE UPPER END OF THE DOOR, AND HAVING AN UPSTANDING ROLLER HANGER AT THE OTHER END PORTION MAKING GUIDING ENGAGEMENT WITH THE UPPER DOOR TRACK; AT LEAST ONE HORIZONTALLY EXTENDING LOWER CRANK ARM ROTATABLY JOURNALED AT ONE END PORTION TO THE LOWER END OF THE DOOR, AND HAVING A DOWNWARDLY DEPENDING ROLLER HOUSING AT THE OTHER END PORTION MAKING SUPPORTING ENGAGEMENT WITH THE LOWER DOOR TRACK; CAM FOLLOWER MEANS DISPOSED ON SAID CRANK ARMS AND EXTENDING BETWEEN SAID END PORTIONS THEREOF; CAM MEANS FOR CAMMING ENGAGEMENT WITH THE CAM FOLLOWER MEANS OF EACH CRANK ARM GUIDINGLY SUPPORTED BY SAID DOOR FOR SLIDING HORIZONTAL MOVEMENT; AND CAM ACUTAING MEANS OPERATIVELY CONNECTIBLE TO SAID CAM MEANS FOR SIMULTANEOUS CAMMING ACTION, SAID CAMMING ACTION URGING EACH OF SAID CRANK ARMS TO ROTATE ABOUT THEIR JOURNALED DOOR CONNECTION THEREBY LATERALLY MOVING SAID DOOR INTO AND OUT OF THE DOOR OPENING IN ACCORDANCE WITH DIRECTION OF SLIDING MOTION OF SAID CAM MEANS. 